Effect of heating rate on the properties of silicon carbide fiber with chemical-vapor-cured polycarbosilane fiber

Silicon carbide (SiC) fiber has recently received considerable attention as promising next-generation fiber because of its high strength at temperatures greater than 1300 °C in air. High-quality SiC fiber is primarily made through a curing and heat treatment process. In this study, the chemical vapor curing method, instead of the thermal oxidation curing method, was used to prepare cured polycarbosilane (PCS) fiber. During the high temperature heat treatment of the cured PCS fiber, varied heating rates of 10, 20, 30, and 40 °C/min were applied. Throughout the process, the fiber remained in the amorphous silicon carbide phase, and the measured tensile strength was the greatest when the oxygen content in the heat-treated fiber was low, due to the rapid heating rate. The fiber produced through this method was also found to have excellent internal oxidation properties. This fast, continuous process shows а great promise for the production of SiC fiber and the development of high-quality products.